Swift 4.1 (and above) Updated answer: Starting from Swift 4.1, all you have to is to conform to the Equatable protocol without the need of implementing the == method. See: SE-0185 – Synthesizing Equatable and Hashable conformance. Example: struct MyStruct: Equatable { var id: Int var value: String } let obj1 = MyStruct(id: 101, value: … Read more
1) Allow two Cacheables of the same type to be compare protocol Cacheable: Equatable { //….// func identifier() -> String } func ==<T : Cacheable>(lhs: T, rhs: T) -> Bool { return lhs.identifier() == rhs.identifier() } Pros This is the simplest solution. Cons You can only compare two Cacheable objects of the same type. This … Read more
To make set of Person you need to make it conform to Equatable and Hashable protocols: class Person: Equatable, Hashable { var Id: Int var Name: String init(id: Int, name: String?) { self.Id = id self.Name = name ?? “” } var hashValue: Int { get { return Id.hashValue << 15 + Name.hashValue } } … Read more
Either the generic approach for comparing two instances of any given struct type: memcmp(&cllc2d1, &second_cllc2d, sizeof(CLLocationCoordinate2D)) or cllc2d1.latitude == cllc2d2.latitude && cllc2d1.longitude == cllc2d2.longitude should work, if you really want to be sure they’re exactly equal. However, given that latitude and longitude are defined as doubles, you might really want to do a “close enough” … Read more
SE-0185 Synthesizing Equatable and Hashable conformance has been implemented in Swift 4.1, so that it suffices do declare conformance to the protocol (if all members are Equatable): enum ViewModel: Equatable { case heading(String) case options(id: String, title: String, enabled: Bool) } For earlier Swift versions, a convenient way is to use that tuples can be … Read more
If you directly implement Equatable on a protocol, it will not longer be usable as a type, which defeats the purpose of using a protocol. Even if you just implement == functions on protocols without Equatable conformance, results can be erroneous. See this post on my blog for a demonstration of these issues: Swift Protocols … Read more